Purging

The atmosphere in the process area (e.g., reactor) – can be efficiently and cost-effectively purged of oxygen and moisture at start-up or shut-down using gaseous nitrogen (GAN).

Filling and purging of plants with this dry gas is completely controllable. No pump is required, so there is no risk of sparks, ignition, or cross-contamination. In addition, the use of Nitrogen [MD(1] [KS2]  ensures that the process sequence "does not react" with either the previously stored substance or the next one in the process flow.

Our unique safety system provides a secure platform for evaluating the flammability properties of a great number of gases, vapors and mixtures. With the PC-based software, application engineers can show you how to reduce shut-downs and start-up time.

When you partner with Linde, you can rely on us for a full-service offering comprising:

• Safety analysis with our safety system
• Tests and feasibility analyses
• Development of a tailored solution
• Advice on the most economical inert gas supply scheme to meet your purity specifications
• Ready-to-run service comprising hardware, installation, and start-up.

In refining, petrochemical and related industries, hydrocarbon and air mixtures from vessels, gas lines, transfer lines and equipment can often present an explosion hazard. Inert gases such as nitrogen provide a safe, precise way to control the atmosphere in these areas. In addition, purging eliminates the need for pumps, and thus the risk of sparks, ignition and cross-contamination with the next step in the process flow. Purging can also be deployed to control the adverse effects of oxidation during welding or additive manufacturing. The ability to measure and control the atmosphere in AM storage cabinets and printer chambers has a major impact on the final quality, structural stability and surface finish of 3D-printed parts. The precise oxygen concentration in powder cabinets and printer chambers can be carefully monitored so the air can be automatically purged to keep the atmosphere at the requisite purity level. In the food industry, purging is used to displace atmospheric gases in mixing/grinding vessels and food packaging.

Any industry that handles flammable gases, vapors and mixtures will have a need for purging. Typical examples include the refining and chemicals industries, which rely heavily on purging for process safety. In fine and specialty chemicals manufacturing, some process stages – such as reactions in stirring tanks – may require the manual charging of solids. Charging ports are purged with inert gases via inert gas locks to stop air/oxygen from entering the vessel along with the bulk material. Shielding gases are also used in welding. Here the weld root and adjacent parent material are purged with a shielding gas in order to protect the penetration bead from becoming contaminated by coming into contact with atmospheric gases during and after welding. The additive manufacturing industry relies on purging for ultra-precise atmosphere control. Purging is also common in the food and beverage industry, where inert gases are flushed into modified atmosphere packages and mixing/grinding vessels to purge the air.

In the refining and chemicals industry, nitrogen and carbon dioxide are used to safely purge potentially explosive hydrocarbon and air mixtures from vessels and pipes. In the food industry, gases such as nitrogen, carbon dioxide and argon are commonly deployed. Looking at welding, argon and nitrogen act as inert gases during root protection, with helium and carbon dioxide sometimes added to improve pitting corrosion resistance. The AM industry typically relies on nitrogen, argon and carbon dioxide plus mixtures of those gases

We provide a full-service offering for all purging applications, spanning secure gas supplies, tailored gas metering equipment, state-of-the-art nozzles plus installation and start-up support.